I tried the 11.6 drivers and my performance plummeted through the floor. I know my sig still says 11.6 but I've gone back to 11.5, where the performance was good.
With the 11.6 drivers, I was getting just over 20 fps average in the Black Death track, which is a little less than half of the normal.
(High setting, for consistency.)
So yes, for me the 11.6 drivers are terrible.